Python获取上个月的第一天和最后一天

代码段：

from datetime import date, timedelta
today = date.today()
last_day_of_last_month = d = date(today.year, today.month, 1) - timedelta(1)
first_day_of_last_month = date(d.year, d.month, 1)

实际代码中的函数：

import calendar
from datetime import date, timedelta

DATE_FMT = "%Y-%m-%d"


def month_day_pair(last_month=False):
    """获取字符串格式的本月初与本月底时间对(或上月初与上月底时间对)"""
    today = date.today()
    year, month = today.year, today.month
    if last_month:
        end = date(today.year, today.month, 1) - timedelta(1)
        start = date(end.year, end.month, 1)
    else:
        start = date(year, month, 1)
        _, last = calendar.monthrange(year, month)
        end = date(year, month, last)
    return f"{start:DATE_FMT}", f"{end:DATE_FMT}"